1. Field of the Invention
The present invention relates to an air-cooled absorption-type water cooling and heating apparatus, and more particularly to an air-cooled absorption-type water cooling and heating apparatus which has an improved coefficient of performance during cooling and heating operations.
2. Description of the Related Art
In a conventional air-cooled absorption-type water cooling and heating apparatus of this type, a high-temperature regenerator is provided with a heating source and communicates with a separator via pipes. The separator is provided with a solution feeding pipe and a vapor pipe having a first on-off valve. The evaporator pipe communicates through a low-temperature regenerator with a forcedly air-cooled condenser by means of a pipe. In addition, the lower-temperature regenerator and the forcedly air-cooled condenser communicate with each other by means of a vapor pipe. The forcedly air-cooled condenser is adapted to be forcedly air-cooled by a cooling fan. The forcedly air-cooled condenser communicates with an evaporator section via a pipe. The evaporator section comprises a first spraying mechanism which receives a refrigerant sent through said pipe and sprays the same onto the surface of a cold-water heat exchanger, as well as a surface section of a cold-water heat exchanger which constitutes an evaporator.
The aforementioned solution feeding pipe is connected to a high-temeprature heat exchanger. An outlet side pipe of the high-temperature heat exchanger is provided with a second on-off valve, and this pipe is connected to the low-temperature regenerator. A condensed solution pipe provided at a bottom of the low-temperature regenerator is connected to a low-temperaure heat exchanger, which is in turn connected to an absorber section via a pipe. The absorber section comprises a cylinder formed coaxially around an outer periphery of the cold-water heat exchanger with a fixed space provided therebetween; fins formed around the outer periphery of the cylinder; a second spraying mechanism which receives a condensed solution sent through the pipe and is adapted to spray the same onto an inner peripheral wall of the cylinder; an inner wall surface of the cylinder constituting an absorber which has the function of absorbing the refrigerant; and a solution tank. This absorber section cools absorption heat generated by absorption action in the absorber, by forcedly supplying air from the air-cooling fan to the fins.
One end of a return pipe is connected to a lower portion of the absorber section, and the other end of this return pipe is connected to the high-temperature regenerator via a circulation pump, the low-temperature heat exchanger, and the high-temperature heat exchanger. The delivery side of a cold-water and hot-water pump is connected to the cold-water heat exchanger and a hot-water heat exchanger provided i the separator. Meanwhile, the suction side of the cold-water and hot-water pump is connected an an air-conditioning load. In addition, the cold-water heat exchanger and the hot-water heat exchanger are connected to a three-way valve, the other end of which is connected to the air-conditioning load.
However, in such a conventional air-cooled absorption-type water cooling and heating apparatus, a coefficient of performance (C. O. P.) during a cooling operation is 1.0 to 1.1, whereas the coefficient of performance (C. O. P.) during a heating operation is 0.8 to 0.85, which is the heating efficiency of the high-temperature regenerator. Here, the coefficient of performance is given by the following formula: ##EQU1##
In addition, since the thermal efficiency is low during a heating operation as compared with a cooling operation, there has been a problem in that the thermal efficiency is undesirably low during the heating operation; hence, such a conventional air-cooled absorption-type water cooling and heating apparatus is not economic. In terms of a general air-conditioning load experienced in a country like Japan, the heating load is about 1.2 times greater than the cooling load, so that, as countermeasures, auxiliary burning is effected by using an additional heating source, and the amount of heating by the high-temperature regenerator is increased. Consequently, there have been problems in that the equipment cost increases, and the control of the apparatus becomes complicated.